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Re: st: statsby slowness
For large numbers of "by groups," I have found it works better/faster to
write my own script that repeatedly pulls the original file from a
tempfile, and then uses a keep statment to restrict the analysis.
Statsby spends too much time looking to see who is in.
P
David Airey wrote:
.
At what point does one give up using statsby? With just three
variables in my data set,
ssrownum, iso_VSV, expression
the following command does OK with 1000 by groups (< 20 cases in a
group), but is not useable with 20,000 by groups.
statsby n=r(N) spearman=r(rho) p=r(p), by(ssrownum): spearman iso_VSV
expression
Why?
I posted something similar a long time ago compared speeds of ttest
with if versus in and versus regress, but I'm not happy at the moment.
--
David C. Airey, Ph.D.
Research Assistant Professor
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--
E. Paul Wileyto, Ph.D.
Assistant Professor of Biostatistics
Tobacco Use Research Center
School of Medicine, U. of Pennsylvania
3535 Market Street, Suite 4100
Philadelphia, PA 19104-3309
215-746-7147
Fax: 215-746-7140
[email protected]
http://mail.med.upenn.edu/~epw/
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